Got a reply. I had asked about 50D, 5D, and 1D Mark IV, along with 550EX, 580EX II, and Vivitar 285HV (in manual mode) flashes. Apparently, they do not test the "off-brand" flashes:

Hello:

The Phottix Odin for Canon is compatible with all Canon cameras and flashes you mentioned.
It was not tested with the Vivitar flashes.

Best Regards,
Phottix Support.

sic0048Registered: Oct 19, 2011Total Posts: 247Country: United States

The Odins should be compatible with the Vivitar flash, but I have to say it would be silly to buy an Odin receiver for non-TTL flashes like the Vivitar. When you use the Odin receiver on a manual flash, it simply works like any other "dumb" trigger - none of the nice TTL and power settings will work with those types of flashes. Since the Phottix Odin system is also compatible with other Phottix lines of "dumb" wireless triggers like the Strattos II, I would suggest getting the much cheaper Strattos II receiver for your Vivitar flash. You can still assign it to one of the three groups that the Odin use. The end result is that the Vivitar flash will fire at the correct time and you will save a lot of money vs buying the more expensive Odin receiver which would give your the exact same result except it costs considerably more.

warjoeRegistered: Aug 23, 2010Total Posts: 56Country: United Kingdom

harrygilbert wrote:
I just sent Phottix an email asking the same question, also compatibility with a range of Canon DSLRs. Will post their reply when I get it. PM me if I forget.

Thanks for your reply, i posted the question a few months back but went ahead and got them for, very happy with them so far just so solid no miss fires and very easy to control the flash power off camera.